Conor McGregor has been key to a lot of big UFC moments in his time with the promotion.

But perhaps none was bigger than when he became the first fighter in UFC history to hold two titles at the same time.

McGregor was featherweight champion following a 12-second knockout of longtime champion Jose Aldo in December 2015. In November 2016, he returned at UFC 205 at Madison Square Garden, arguably the most famous fight venue in the world, and took the lightweight crown, too.

McGregor dominated Eddie Alvarez and eventually put him away with a second-round TKO to become a dual champ in front of a packed house, many of whom were there in support of the Irish superstar.

McGregor (22-4 MMA, 10-2 UFC) returns later this month to headline UFC 257 in a rematch with Dustin Poirier (26-6 MMA, 18-5 UFC), whom he beat with a first-round knockout at UFC 178 in September 2014. UFC 257 takes place Jan. 23 at Etihad Arena at Yas Island in Abu Dhabi. The main card airs on pay-per-view following prelims on ESPN and ESPN+.

But before that event, which will be the UFC’s first pay-per-view of 2021 and McGregor’s first fight since January 2020, check out his historic finish of Alvarez in the video above.